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Methoxytetrafluoroethane is a kind of new chemical for synthesizing fluorine containing surfactants,and it is synthesized by tetrafluoroethene and methanol.There is a mass of methanol existing in the final product,so methanol has to be separated from the product in order to get pure methoxytetrafluoroethane.Considerating that methanol is strong water-solubility and water is practically immiscible with methoxytetrafluoroethane,water is selected as a solvent to extract methanol from the mixture of methoxytetrafluoroethane and methanol.The study on liquid-liquid equilibrium (LLE) for the system of methoxytetrafluoroethane+methanol+water is important for methoxytetrafluoroethane refining by extraction.Therefore,basic data for the ternary system of methoxytetrafluoroethane-methanol-water at 293.2K and 303.2K was measured under atmospheric pressure in an equilibrium cell (as shown in Fig.1 and Fig.2).The solution concentrations were determined by gas chromatography.The experimental data shows that high temperature has a negative effect on the recovery of methanol.The extraction should be carried out in a relatively low temperature.The extraction experiments were carried out in a packed extraction column with diameter 13mm and effective height 0.8m.The results show that as the water flowrate goes up,the concentration of methanol in oil phrase reduces,and methoxytetrafluoroethane purity goes up.Using about 10(wt)% of methanol raw material solution and pure water as feeds,the concentration of methanol in raffinate phrase as low as 0.10(wt)% and methanol recovery rate 99.34% are obtained in the extraction process (as shown in Table 1).The methoxytetrafluoroethane purification process using water as an extractant is a very efficient and economic method.The experimental research provides basic information for scale-up of the process.